Connection structure of chain for transportation

ABSTRACT

In a conveyor chain coupling structure, a block link A has a connecting rod ( 2 ) provided at one of conveying-directional ends thereof to project in the conveying direction and a coupling bore ( 5 ) formed at the other conveying-directional end. A pair of toroidal bush bearings ( 25, 30 ) is provided and a spherical bush ( 2 ) to be fixed to the connecting rod ( 2 ) is provided between the pair of toroidal bush bearings ( 25, 30 ). The first toroidal bush bearing ( 25 ) is fitted slidably on a portion, at the side of the other conveying-directional end, of the spherical bush ( 20 ) while the second toroidal bush bearing ( 30 ) is fitted at the spherical concave surface ( 31 ) thereof slidably on a portion, at the side of the one conveying-directional end, of the spherical bush ( 20 ). Owing to this construction, the coupled parts will not rattle, which will thus cause no pulsation or noise but will assure a smooth relative oscillation or reciprocal relative rotation of the block links. Further, this conveyor chain coupling structure is simplified, robust and durable than ever, and can be assembled and disassembled easily even in a narrow space. Also, the maintenance and the like can be made easily. Such jobs will be completed in a reduced time. Thus, the coupling structure very easy to handle and can be designed highly compact. Further, since it is suitable for mass production with a reduced cost of manufacture and can implement an inexpensive conveyor chain.

FIELD OF THE INVENTION

[0001] The present invention generally relates to a conveyor chainformed from a plurality of block links. In the conveyor chain of thistype, adjacent block links are coupled to each other for relativeoscillation in all directions about a conveying direction as well as forreciprocal relative rotation about the conveying direction. Moreparticularly, the present invention is directed to an easier-to-handleconveyor-chain coupling structure in which the adjacent block links canbe oscillated smoothly in relation to each other and also reciprocallyrotated smoothly in relation to each other with less rattling at thecoupled parts thereof.

BACKGROUND ART

[0002] The conveyor-chain coupling structure of the above type is knownfrom, for example, the Japanese Published Unexamined Application No.513426 of 1998 in which there is disclosed a product support combinedwith each of multiple similar conveyance units serially coupled to eachother in the form of an endless chain to simultaneously convey productswhile rotating the latter.

[0003] The above product support includes a mount plate with means forcoupling the mount plate to two adjacent mount plates before and afterthe mount plate in consideration, a body fixed to the mount plate, and arod supported in the body to be axially movable and freely rotatable andhaving a grip end formed to be removably fixed to an open end of theproduct.

[0004] The coupling means includes a coupling stem provided at one endof the mount plate to support a spherical cap-shaped coupling head to beborn by the mount plate adjacent to the one end, and a seat provided atthe other end of the mount plate, formed to have a spherical shapecomplementing the spherical cape shape of the coupling head and havingan axial opening formed therein to allow free pass of the coupling stemof the mount plate adjacent to the other end of the mount plate inconsideration. The coupling stem is supported for the sphericalcap-shaped coupling head to freely be rotatable. A bearing plate isfixed perpendicularly to a free end of the coupling stem by a fixingmeans. The bearing plate extends generally parallel to a surface of thecoupling head opposite to the spherical cap-shaped surface. Further, atoroidal rotating shaft is inserted between the opposite surfaces of thecoupling head and bearing plate coaxially with the coupling stem.

[0005] While a load is being applied to the aforementioned productsupport in a direction in which the adjacent mount plates will be movedaway from each other, the coupled parts rattle less. However, when aload is applied to the product support in a direction in which theadjacent mount plates will be moved toward each other, the coupled partsrattle much, causing a pulsation, noise or the like during travel of theconveyor chain. In addition, since the coupling between the mount platesis complicated, it is very troublesome to assemble and disassemble thecoupling parts and thus maintenance of the coupling parts are not easy.Therefore, the assembling, disassembling and maintenance take a longtime.

DISCLOSURE OF THE INVENTION

[0006] Accordingly, the present invention has an object to overcome theabove-mentioned drawbacks of the related art by providing a conveyorchain coupling structure in which block links can oscillate smoothly inrelation to each other and reciprocally rotate smoothly in relation toeach other, and which is simple in construction, easy to handle andhighly durable.

[0007] The above object can be attained by providing a couplingstructure of a conveyor chain formed from a plurality of block links (A)coupled to each other, in which adjacent block links (A) are coupled toeach other for relative oscillation in all directions about a conveyingdirection as well as for reciprocal relative rotation about theconveying direction, the coupling structure including according to thepresent invention a connecting rod (2) projecting from one ofconveying-directional ends of the block link (A), a coupling bore (5)formed at the other conveying-directional end of the block link (A), afirst toroidal bush bearing (25) having a spherically concave innersurface (26) and provided in the coupling bore (5) at the side of theother conveying-directional end of the block link (A), a second toroidalbush bearing (30) having a spherically concave inner surface (31)provided in the coupling bore (5) at the side of the oneconveying-directional end of the block link (A), a stopper (35) providedto block the first and second toroidal bush bearings (25, 30) fromcoming out of the coupling bore (5), and a spherical bush (20) having aspherically convex outer surface (21), provided between the pair oftoroidal bush bearings (25, 30) and fixed to the free end of theconnecting rod (2), the first toroidal bush bearing (25) being fitted atthe spherical concave surface (26) thereof slidably on a portion, at theside of the other conveying-directional end, of the spherically convexsurface (21) of the spherical bush (20), and the second toroidal bushbearing (30) being fitted at the spherical concave surface (31) thereofslidably on a portion, at the side of the one conveying-directional end,of the spherically convex surface (21) of the spherical bush (20).

[0008] In the above conveyor chain coupling structure according to thepresent invention, whether a load is applied to the conveyor chain in adirection in which the adjacent block links (A) will be moved away fromeach other or in a direction in which they will be moved toward eachother, the coupled parts will not rattle, which will thus cause nopulsation or noise during travel of the conveyor chain but will assure asmooth relative oscillation or reciprocal relative rotation of the blocklinks (A).

[0009] Further, the coupling between the block links (A) is moresimplified, robust and durable than ever, and can be assembled anddisassembled more easily. Also, the maintenance and the like can be mademore easily. Such jobs will be completed in a reduced time. Thus, thepresent invention provides a conveyor chain coupling structure very easyto handle.

[0010] More specifically, in the coupling bore (5), the first toroidalbush bearing (25) provided at the side of the otherconveying-directional end of the block link (A) and second toroidal bushbearing (30) provided at the side of the one conveying-directional endof the block link (A) are blocked by the stopper (35) from coming outfrom the coupling bore (5), and the spherical bush (20) provided betweenthe pair of toroidal bush bearings (23, 30) is fixed to the free end ofthe connecting rod (2) so that the first toroidal bush bearing (25) isslidable at the spherical concave surface (26) thereof on a portion, atthe side of the other conveying-directional end, of the sphericallyconvex surface (21) of the spherical bush (20) while the second toroidalbush bearing (30) is slidable at the spherical concave surface (31)thereof on a portion, at the side of the one conveying-directional end,of the spherically convex surface (21) of the spherical bush (20). Thus,the spherical bush (20) can easily be installed between the pair oftoroidal bush bearings (25, 30) and this assembly can easily beinstalled into the small coupling bore (5). This installation can bemade in any narrow place. Thus, the conveyor chain coupling structureitself can be designed more compact, and also since it is suitable formass production with a reduced cost of manufacture, an inexpensiveconveyor chain can be provided.

[0011] In the conveyor chain coupling structure according to the presentinvention, the coupling bore (5) should have a circular inner wallformed about the conveying direction and on which the toroidal bushbearings (25, 30) in pair are slidable at the outer surfaces thereof andthey are reciprocally rotatable about the conveying direction inside thecoupling bore (5).

[0012] In the above coupling structure, the adjacent block links (A) canbe rotated more smoothly in relation to each other about the conveyingdirection.

[0013] In the above conveyor chain coupling structure according to thepresent invention, the coupling bore (5) should have an engagement step(6) formed along one open end thereof at the side of the otherconveying-directional end of the block link (A) and also a stopperrecess (7) formed along the open end thereof at the oneconveying-directional end of the block link (A) and in which the stopper(35), generally C-shaped, is removably fitted, so that the engagementstep (6) and stopper (35) work together to prevent the pair of toroidalbush bearings (25, 30) from coming out of the coupling bore (5).

[0014] In the above coupling structure, the pair of toroidal bushbearings (25, 30) can stably be provided inside the coupling bore (5)and can positively be blocked from coming out of the coupling bore (5).In addition, the stopper (35) can easily be fitted into or removed fromthe stopper recess (7), which will greatly contribute to easierreplacement of the toroidal bush bearings (25, 30) and spherical bush(20) as well as to easier and time-saving assembling, disassembling,maintenance, etc. of such components.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015]FIG. 1 is an exploded perspective view of an embodiment of theconveyor chain coupling structure according to the present invention.

[0016]FIG. 2 is a partially fragmentary plan view of the conveyor chaincoupling structure in FIG. 1.

[0017]FIG. 3 is a partially fragmentary rear view of an example of theblock link having the coupling structure according to the presentinvention and to which a product support is installed.

[0018]FIG. 4 is a partially fragmentary side elevation of the conveyorchain coupling structure in FIG. 1.

BEST MODE FOR CARRYING OUT THE INVENTION

[0019] The embodiment of the conveyor chain coupling structure accordingto the present invention will be described below with reference to theaccompanying drawings.

[0020] The embodiment going to be explained herebelow is an applicationof the present invention to a coupling structure for coupling aplurality of block links A to each other, for example, a couplingstructure for a conveyor chain constructed for reciprocal relativerotation of the block links A in planes perpendicular to a direction inwhich products are to be conveyed, such as a conveyor chain for use toconvey container products.

[0021] As shown, the coupling structure includes a connecting rod 2provided at one end of the block link A and which projects in theconveying direction, a coupling bore 5 formed at the otherconveying-directional end of the block link A, a first toroidal bushbearing 25 having a spherically concave inner surface 26 and provided inthe coupling bore 5 at the side of the other conveying-directional endof the block link A, a second toroidal bush bearing 30 having aspherically concave inner surface 31 provided in the coupling bore 5 atthe side of the one conveying-directional end of the block link A, astopper 35 provided to block the first and second toroidal bush bearings25 and 30 from coming out of the coupling bore 5, and a spherical bush20 having a spherically convex outer surface 21, provided between thepair of toroidal bush bearings 25 and 30 and fixed to the free end ofthe connecting rod 2.

[0022] The first toroidal bush bearing 25 is fitted at the sphericalconcave surface 26 thereof slidably on a portion, at the side of theother conveying-directional end, of the spherically convex surface 21 ofthe spherical bush 20, and the second toroidal bush bearing 30 is fittedat the spherical concave surface 31 thereof slidably on a portion, atthe side of the one conveying-directional end, of the spherically convexsurface 21 of the spherical bush 20. Thus, adjacent block links A arecoupled to each other for relative oscillation in all directions about aconveying direction as well as for reciprocal relative rotation aboutthe conveying direction.

[0023] The block link A includes a block-shaped link body 1 formed froma metal, synthetic resin or any other suitable material, for example.The link body 1 has the connecting rod 2 joined thereto at the center ofthe front face thereof. Also, the link body 1 has a shaft 10 joined toeither lateral sides thereof and on which a traveling roller 12 can beinstalled. The link body 1 has the coupling bore 5 formed in the centerof the rear end thereof. The coupling bore 5 is open at the rear end ofthe link body 1. Further, the link body 1 has a vertical mount hole 15formed through it.

[0024] The connecting rod 2 can be inserted through a hole 22 formedthrough the spherical bush 20. It is a round shaft whose axis is alignedwith the conveying direction of the conveyor chain and has a thread 3formed at the free end portion thereof and to which the spherical bush20 can readily be fixed with a nut 36.

[0025] Note that the base portion of the connecting rod 2 is formed tohave a larger diameter than the through-hole 22 in the spherical bush 20such that the spherical bush 20 can be fixed at some distance from thefront face of the link body 1 and also can be fixed positively byfastening the nut 36.

[0026] The coupling bore 5 has a circular inner wall whose center lineis aligned with the axis of the connecting rod 2. The coupling bore 5has an engagement step 6 formed at the other conveying-directional endthereof (along the edge of the opening in the rear end face of the linkbody 1) to block the toroidal bush bearing 25 from coming off and also astopper recess 7 formed at the one conveying-directional end thereof(along the edge of the opening in the front end face of the link body 1)to removably receive the generally C-shaped stopper 35.

[0027] That is, the engagement step 6 and stopper 35 fitted in thestopper recess 7 work together to prevent the pair of toroidal bushbearings 25 and 30 from rattling while moving in the conveying directioninside the coupling bore 5.

[0028] Also, since the toroidal bush bearings 25 and 30 in pair areshaped to slide at the outer surfaces thereof on the inner wall surfaceof the coupling bore 5, they are reciprocally rotated about theconveying direction inside the coupling bore 5 so that adjacent blocklinks A can reciprocally be rotated more smoothly in relation to eachother in the conveying direction.

[0029] The shaft 10 is shaped in the form of a short cylinder, forexample. It is internally threaded (indicated with a reference 11) atthe free end portion thereof. The roller 12 can readily be installed onthe shaft 10 by screwing a bolt 13 (flanged bolt, for example) into theinternally threaded portion 11 of the shaft 10.

[0030] Note that the roller 12 uses a bearing or the like.

[0031] The mount hole 15 receives a product support B or the like. Themount hole 15 is formed to communicate with the one conveying-directionend of the coupling bore 5. More specifically, the block links A can becoupled to each other using the space in the mount hole 15. After theblock links A are thus coupled to each other, the product support B isto be installed in the mount hole 15.

[0032] The spherical bush 20 is formed from a metal, synthetic resin orany other suitable material, for example, to a shape which will resultfrom cutting a sphere along a pair of parallel flat planes. Thethrough-hole 22 is formed through the spherical bush 20 in the center ofthe flat planes.

[0033] The pair of toroidal bush bearings 25 and 30 is formed from ametal, synthetic resin or any other suitable material, for example, tohave a toroidal shape for fitting in the coupling bore 5, and has thespherically concave inner surfaces 26 and 31, respectively, formedcorrespondingly to the sliding spherically convex surface 21 being theouter surface of the spherical bush 20.

[0034] Note that the spherically concave inner surface 26 of the firsttoroidal bush bearing 25 and that 31 of the second toroidal bush bearing30 have a curved shape which will result from bisecting a sphere. Thatis, by inserting the first toroidal bush bearing 25, spherical bush 20,and the second toroidal bush bearing 30 in this order into the couplingbore 5 and fitting the stopper 35 into the stopper recess 7, it ispossible to easily install the toroidal bush bearings 25 and 30 and thespherical bush 20 into the coupling bore 5.

[0035] The stopper 35 is formed from a suitable metal plate to have agenerally C shape, for example. Owing to the elastic deformation, thestopper 35 can removably be fitted into the stopper recess 7 in thecoupling bore 5. As shown, a washer 37 is fitted on the connecting rod 2between the spherical bush 20 and nut 36.

[0036] Note that the shapes, dimensions, materials or disposed positionsof the block link A, link body 1, connection rod 2, thread 3, couplingbore 5, engagement step 6, stopper recess 7, mount hole 15, sphericalbush 20, sliding spherically convex surface 21, through-hole 22,toroidal bush bearings 25 and 30, spherically concave surfaces 26 and31, stopper 35, nut 36 and washer 37 are not limited to those havingbeen described in the foregoing concerning the aforementioned embodimentof the conveyor chain coupling structure according to the presentinvention but may of course be modified or altered without departingfrom the scope and spirit of the present invention.

INDUSTRIAL APPLICABILITY

[0037] As having been described in the foregoing, the present inventionprovides such a conveyor chain coupling structure that whether a load isapplied to the conveyor chain in a direction in which the adjacent blocklinks will be moved away from each other or in a direction in which theywill be moved toward each other, the coupled parts will not rattle,which will thus cause no pulsation or noise during travel of theconveyor chain but will assure a smooth relative oscillation orreciprocal relative rotation of the block links.

[0038] Further, this conveyor chain coupling structure is moresimplified, robust and durable than ever, and can be assembled anddisassembled more easily. Also, the maintenance and the like can be mademore easily. Such jobs will be completed in a reduced time. Thus, theconveyor chain coupling structure very easy to handle and can bedesigned highly compact. Further, since it is suitable for massproduction with a reduced cost of manufacture and can implement aninexpensive conveyor chain, the present invention is extremely usefullyapplicable in the field of conveyor chains used in various industries.

1. A coupling structure of a conveyor chain formed from a plurality ofblock links coupled to each other, in which adjacent block links arecoupled to each other for relative oscillation in all directions about aconveying direction as well as for reciprocal relative rotation aboutthe conveying direction, the coupling structure comprising: a connectingrod projecting from one of conveying-directional ends of the block link;a coupling bore formed at the other conveying-directional end of theblock link; a first toroidal bush bearing having a spherically concaveinner surface and provided in the coupling bore at the side of the otherconveying-directional end of the block link; a second toroidal bushbearing having a spherically concave inner surface provided in thecoupling bore at the side of the one conveying-directional end of theblock link; a stopper provided to block the first and second toroidalbush bearings from coming out of the coupling bore; and a spherical bushhaving a spherically convex outer surface, provided between the pair oftoroidal bush bearings and fixed to the free end of the connecting rod;the first toroidal bush bearing being fitted at the spherical concavesurface thereof slidably on a portion, at the side of the otherconveying-directional end, of the spherically convex surface of thespherical bush; and the second toroidal bush bearing being fitted at thespherical concave surface thereof slidably on a portion, at the side ofthe one conveying-directional end, of the spherically convex surface ofthe spherical bush.
 2. The conveyor chain coupling structure as setforth in claim 1, wherein the coupling bore has a circular inner wallformed about the conveying direction and on which the toroidal bushbearings in pair are slidable at the outer surfaces thereof and they arereciprocally rotatable about the conveying direction inside the couplingbore.
 3. The conveyor chain coupling structure as set forth in claim 1or 2, wherein the coupling bore has an engagement step formed along oneopen end thereof at the side of the other conveying-directional end ofthe block link and also a stopper recess formed along the open endthereof at the one conveying-directional end of the block link and inwhich the stopper, generally C-shaped, is removably fitted, so that theengagement step and stopper work together to prevent the pair oftoroidal bush bearings from coming out of the coupling bore.